In recent years, extensive researches on mobile carriers having wheels and their related control method and mobile capability are conducted, and their applications cover the mobile carriers for handicaps, elderly people or robots, and the carries of this sort are expected to be used extensively in our daily life. In 2007, The Ministry of Economy, Trade and Industry (Japan) decided to reserve a budget of two thousand million yens to subsidize the research and development of new-generation artificial intelligent robots such as police robots and tour-guide robots. To make the robots more practical and achieve the target of commercializing the robots in 2015, the University of Tokyo and seven major corporations started their research programs on robots for the aging population of the society and intended to spend 10 to 15 years to develop a robot that can do housework and expected to develop a robot that can determine and cross a street safely by 2016. The budget of the first three years of the research is up to 8.7 million U.S. dollars, and it is the largest scale of joint research on robot technologies between Japanese universities and the industry. The U.S. National Science Foundation sponsored Carnegie Mellon University and University of Pittsburgh with 1.5 million U.S. dollars to establish the Institute for Quality of Life and develop the household robot technology. The objective of the research program is to apply technologies innovatively to help professionals in different areas and handicaps who need helps in their daily life.
A traditional wheeled carrier such as a wheelchair generally uses the wheels on both left and right sides of the wheelchair to drive the wheelchair, and the differential wheel of turns can be used to control the driving direction. Such method can maintain stable movements easily, and thus is used extensively. However, the method involves a very complicated process to move the carrier sideway and also encounters the problem of making turns. The carrier must be turned to a traveling direction first before reaching the traveling direction towards the destination, and then the carrier is returned to the original direction, and it is obvious that the confirmation of the route becomes very important. As a result, the carriers of this structure only gives two degrees-of-freedom (DOF) which is the simplest control method, and different rotating speeds are provided to the wheels to control the carrier to move forward, make turns and back up. The carrier can be rotated at any point, but it still cannot be moved sideway. If it is necessary to move in an environment with many obstacles and a crowd of people, the movements of the carriers of the sort are limited substantially. Particularly, when the carrier is used in a small home or a crowded public place, the inflexibility of movements will become a major drawback.
Therefore, the present invention intends to find a way of using an omnidirectional movement control system to operate with a mobile platform having omnidirectional wheels, so that the mobile platform can be moved in any direction and rotated in different directions, so as to overcome the shortcomings and the inflexible movement of conventional wheeled carriers.